The invention relates to a method and apparatus for the ventilation of fuel supply pumps. Fuel supply pumps are already known in which the fuel pumping system and the electromotor are enclosed in a cup-shaped housing. It has already been proposed to embody the fuel supply pump in two stages, where the first stage is conventionally a lateral channel pump, while the second pump, coupled in series therewith and effecting the desired high final pressure, operates as a roller piston pump. Both fuel pumps, the lateral channel pump and the roller piston pump, are preferably arranged on a side that is oriented toward the collector of the driving electromotor.
Problems arise with respect to the ventilation of the lateral channel in such pumps, in particular in two-stage fuel supply pumps having a forwardly disposed lateral channel pump.